Paris Hilton and Kim Kardashian Host Rival Kentucky Derby Parties

2009 Kentucky Derby parties are most certainly one of the highlights of the annual event; it's not just the outfits at the horse races that matter (although we do love any excuse to wear big brimmed hats), it's the Kentucky Derby eve gala fashion that we're really curious about. After all, these are star-studded affairs and the biggest excuse of the season to go over the top with your garb.

Some of the most anticipated celebrity fashion at the 2009 Kentucky Derby, which take places today in Louisville, will undoubtedly be the Derby hats and gowns worn by socialites like Paris Hilton and Kim Kardashian. But since the former best friends will be hosting rivaling 2009 Kentucky Derby parties, it's sure to be a battle of the costumes.

"Paris is cohosting the Barnstable Brown Derby Eve bash with boyfriend Doug Reinhardt. The charity gala donates money to benefit diabetes research," eonline says. "Kim is on duty at the Derby Spectacular shindig at Glassworks (hosted last year by Jenny McCarthy)."